Answer:
12.0 tablet computers/month
Step-by-step explanation:
The average price of the tablet 25 months from now will be:
Next, we determine the rate at which the quantity demanded changes with respect to time.
Using Chain Rule (and a calculator)
![\dfrac{dx}{dp}= \dfrac{d}{dp}\left[{ \dfrac { 100 } { 9 } \sqrt { 810,000 - p ^ { 2 } } }\right] =-\dfrac{100}{9}p(810,000-p^2)^{-1/2}](https://tex.z-dn.net/?f=%5Cdfrac%7Bdx%7D%7Bdp%7D%3D%20%5Cdfrac%7Bd%7D%7Bdp%7D%5Cleft%5B%7B%20%5Cdfrac%20%7B%20100%20%7D%20%7B%209%20%7D%20%5Csqrt%20%7B%20810%2C000%20-%20p%20%5E%20%7B%202%20%7D%20%7D%20%7D%5Cright%5D%20%3D-%5Cdfrac%7B100%7D%7B9%7Dp%28810%2C000-p%5E2%29%5E%7B-1%2F2%7D)
![\dfrac{dp}{dt}=\dfrac{d}{dt}\left[\dfrac { 400 } { 1 + \dfrac { 1 } { 8 } \sqrt { t } } + 200 \right]=-25\left[1 + \dfrac { 1 } { 8 } \sqrt { t } \right]^{-2}t^{-1/2}](https://tex.z-dn.net/?f=%5Cdfrac%7Bdp%7D%7Bdt%7D%3D%5Cdfrac%7Bd%7D%7Bdt%7D%5Cleft%5B%5Cdfrac%20%7B%20400%20%7D%20%7B%201%20%2B%20%5Cdfrac%20%7B%201%20%7D%20%7B%208%20%7D%20%5Csqrt%20%7B%20t%20%7D%20%7D%20%2B%20200%20%5Cright%5D%3D-25%5Cleft%5B1%20%2B%20%5Cdfrac%20%7B%201%20%7D%20%7B%208%20%7D%20%5Csqrt%20%7B%20t%20%7D%20%5Cright%5D%5E%7B-2%7Dt%5E%7B-1%2F2%7D)
Therefore:
![\dfrac{dx}{dt}= \left[-\dfrac{100}{9}p(810,000-p^2)^{-1/2}\right]\left[-25\left[1 + \dfrac { 1 } { 8 } \sqrt { t } \right]^{-2}t^{-1/2}\right]](https://tex.z-dn.net/?f=%5Cdfrac%7Bdx%7D%7Bdt%7D%3D%20%5Cleft%5B-%5Cdfrac%7B100%7D%7B9%7Dp%28810%2C000-p%5E2%29%5E%7B-1%2F2%7D%5Cright%5D%5Cleft%5B-25%5Cleft%5B1%20%2B%20%5Cdfrac%20%7B%201%20%7D%20%7B%208%20%7D%20%5Csqrt%20%7B%20t%20%7D%20%5Cright%5D%5E%7B-2%7Dt%5E%7B-1%2F2%7D%5Cright%5D)
Recall that at t=25, 
Therefore:
![\dfrac{dx}{dt}(25)= \left[-\dfrac{100}{9}\times 446.15(810,000-446.15^2)^{-1/2}\right]\left[-25\left[1 + \dfrac { 1 } { 8 } \sqrt {25} \right]^{-2}25^{-1/2}\right]\\=12.009](https://tex.z-dn.net/?f=%5Cdfrac%7Bdx%7D%7Bdt%7D%2825%29%3D%20%5Cleft%5B-%5Cdfrac%7B100%7D%7B9%7D%5Ctimes%20446.15%28810%2C000-446.15%5E2%29%5E%7B-1%2F2%7D%5Cright%5D%5Cleft%5B-25%5Cleft%5B1%20%2B%20%5Cdfrac%20%7B%201%20%7D%20%7B%208%20%7D%20%5Csqrt%20%7B25%7D%20%5Cright%5D%5E%7B-2%7D25%5E%7B-1%2F2%7D%5Cright%5D%5C%5C%3D12.009)
The quantity demanded per month of the tablet computers will be changing at a rate of 12 tablet computers/month correct to 1 decimal place.
Answer:
The answer is 120, 80, 100, 180, 40, 0, 240
Step-by-step explanation:
In this situation, quadrupling means to times everything (everything which is 30, 20, 25, 45, 10, 0, 60) by 4, which will give you 120, 80 ,100 ,180, 40, 0, 240
Answer:
We can have two cases.
A quadratic function where the leading coefficient is larger than zero, in this case the arms of the graph will open up, and it will continue forever, so the maximum in this case is infinite.
A quadratic function where the leading coefficient is negative. In this case the arms of the graph will open down, then the maximum of the quadratic function coincides with the vertex of the function.
Where for a generic function:
y(x) = a*x^2 + b*x + c
The vertex is at:
x = -a/2b
and the maximum value is:
y(-a/2b)
(1,52)(-1,-52) (2,26)(-2,-26)(4,13)(-4,-13)(1/2,104), etc etc etc
Answer: 120
Step-by-step explanation:
From the question, we are informed that there are 10 people in a math club and that three people will be chosen for the Pi Day committee.
The number of different ways that the club members can structure the committee goes thus:
This can be solved by:
nCr = n! / r! (n - r)!
where n = 10
r = 3
= n! / r! (n - r)!
= 10! / 3! (10 - 3)!
= (10 × 9 × 8) / (3 × 2)
=120
